In data communication systems, it is often useful to modularize interface electronics and other interface elements in a data communication module. For example, in an optical data communication system, an opto-electronic transceiver module may include a light source such as a laser, and a light detector such as a photodiode, and may also include driver and receiver circuitry associated with the laser and photodiode. To use such an opto-electronic transceiver module, an optical fiber cable is plugged into a port in the module. Such a module also includes electrical contacts that can be coupled to an external electronic system.
Another example of a data communication module is an Ethernet transceiver module. To use an Ethernet transceiver module, an Ethernet cable, which may have an electrical rather than an optical connector, is plugged into a port in the module. The module may include signal conditioning electronics. Such a module also includes electrical contacts that can be coupled to an external electronic system.
Some data communication modules are configured to be plugged into a cage or other receptacle. A standard data communication module configuration commonly referred to in the art as Small Form Factor Pluggable (SFP) includes an elongated housing having a generally rectangular profile. An SFP module is pluggable into a bay in the front panel of a cage having an array of such bays. The nose end of the module includes a mechanism that latches the module in the cage. The mechanism typically comprises a pin on the module housing and a catch on the cage. As a user pushes or inserts the module into the cage, the pin engages an opening in the catch to latch the module in place in the cage. To release or unlatch the module from the cage, the user flips a pivoting bail on the module or otherwise moves a mechanism on the module to cause the pin and the catch to disengage from each other. As the bail or other user-operated mechanism is more directly involved in de-latching the module from the cage rather than latching the module in the cage, the mechanism as a whole is typically referred to as a “de-latch mechanism.”
In some modules, the bail can be used as a handle to extract the module from the cage after the module has been de-latched. However, in an instance in which many modules are plugged into the cage, forming a dense array, it may be difficult to grip the bail or otherwise grip a portion of the module to extract it from the cage. To address this potential problem, a module can be provided with an elongated handle or tab that extends from the nose end of the module. A user can readily grip the tab to more easily extract the module from the cage.
It has been suggested to provide a tab that a user not only can pull to extract the module from the cage but also push to insert the module into the cage. Providing such a push-pull tab poses challenges. A tab of the above-described elongated type that a user can pull (in the direction of an axis) to extract the module is commonly made of a flexible or compliant plastic that deflects or flexes in response to forces applied in directions other than along the axis. For example, the tab flexes if a downward or upward force is applied to the tab, as might occur if, for example, the person's hand or arm were inadvertently to brush against the tab while the person was attempting to reach for the tab of another module. It is believed important that the tab be flexible for several reasons. First, a rigid tab would be susceptible to breakage or similar damage from such off-axis forces. Similarly, a rigid tab would need to be strong enough to resist breakage or similar damage if a person were to attempt to hold the module only by its tab, demanding that the tab support the entire weight of the module. Second, a rigid tab could transmit such off-axis forces in a way that could inadvertently dislodge the module from the cage. Third, a rigid tab could transmit such off-axis forces to the cage in a way that could damage the cage.